With Help From Jodie Foster, SETI Resumes Search for Alien Life

The Alan Array of the Seti Institute will only be of much use if they can build out to 350 Arrays from the current 42. Supporting just $200,000 to keep the 42 operational isn't going to do anything but keep the pretty useless current array working!

Also just so you know SETI @ home doesn't rely on the Allan Array - they're separate.

The SETI Institute was pretty much a boondoggle: Alan gave them money to build an array of 350 telescopes, but they screwed up and only built 42, essentially wasting the funds. Here's other info: http://www.skyandtelescope.com/resources/seti/3304581.html

That's a good choice of wording :) It may or may not apply, it depends on the antenna.

The physical basis for all inverse square laws - gravity, electrical charge attraction, radio signal strength, is actually geometric. They are all measurements of some kind of flux, so you have a certain quantity of signal, which then has to be divided by the surface area of the sphere surrounding the source. As the distance from the source increases, the surface area of the sphere increases as the square of the radius.

So yes, if the source is in fact a point source radiating equally in all directions, the signal drops off as per the inverse square law. But, if you have a very tight beam, then the signal strength is maintained for a lot longer. In that case, signal loss is caused by diffusion, and by attenuation due to hitting matter that is in the beam. A highly parallel laser beam of a not unreasonable power level, preferably generated from a satellite orbiting outside any atmosphere, should be capable of being received pretty much anywhere in the galaxy. Alternatively, if you have a big enough dish, you could do the same thing with radio waves. Indeed, it is estimated that Arecibo is capable of communicating with any other Arecibo-style dish in a roughly 100 hundred light year diameter around the Earth, if the two happen to be pointed at each other, and one is transmitting whilst the other is receiving... http://www.cplire.ru/html/ra&sr/irm/limitations.html

And that's with a measly 1000kW radio, weaker than most primary radars used today.

There's a couple of agencies on Earth that spend their time capturing human communications. It's a very difficult task and they need more than $ 200,000 to operate.

Now I understand we just want to detect with a good degree of certitude that a transmission is intelligent but not human. We don't care about descrambling it.

Yet, I think it's an almost impossible task because those communications will most likely be compressed and ciphered and therefore look like noise.